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Title: On the hysteresis in E to H and H to E transitions and the multistep ionization in inductively coupled plasma

Abstract

Plasma densities, E to H and H to E transition coil currents, and electron energy distribution functions (EEDFs) are measured at various argon pressures in an inductively coupled plasma. The measured plasma density versus coil current shows that the hysteresis during the E-H transition is clearly observed only when the pressure is sufficiently high. At low gas pressures the hysteresis is not obvious. The measured EEDFs show that when the hysteresis is obvious (high pressures), electrons whose energy is not sufficient for excitation or ionization of the ground state atom are strongly depleted in the H mode. This depletion may be caused by multistep ionization. However, for the case where the hysteresis is not obvious (low pressures), the depletion due to multistep ionization is also not present. These experimental results show that the multistep ionization is a dominant factor in the E-H transition hysteresis.

Authors:
; ; ;  [1]
  1. Department of Electrical and Computer Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea, Republic of)
Publication Date:
OSTI Identifier:
20971914
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 90; Journal Issue: 19; Other Information: DOI: 10.1063/1.2734501; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ARGON; ELECTRONS; ENERGY SPECTRA; GROUND STATES; H-MODE PLASMA CONFINEMENT; HYSTERESIS; IONIZATION; LANGMUIR PROBE; PLASMA; PLASMA DENSITY

Citation Formats

Lee, Min-Hyong, Lee, Kyeong Hyo, Hyun, Dong-Seok, and Chung, Chin-Wook. On the hysteresis in E to H and H to E transitions and the multistep ionization in inductively coupled plasma. United States: N. p., 2007. Web. doi:10.1063/1.2734501.
Lee, Min-Hyong, Lee, Kyeong Hyo, Hyun, Dong-Seok, & Chung, Chin-Wook. On the hysteresis in E to H and H to E transitions and the multistep ionization in inductively coupled plasma. United States. doi:10.1063/1.2734501.
Lee, Min-Hyong, Lee, Kyeong Hyo, Hyun, Dong-Seok, and Chung, Chin-Wook. Mon . "On the hysteresis in E to H and H to E transitions and the multistep ionization in inductively coupled plasma". United States. doi:10.1063/1.2734501.
@article{osti_20971914,
title = {On the hysteresis in E to H and H to E transitions and the multistep ionization in inductively coupled plasma},
author = {Lee, Min-Hyong and Lee, Kyeong Hyo and Hyun, Dong-Seok and Chung, Chin-Wook},
abstractNote = {Plasma densities, E to H and H to E transition coil currents, and electron energy distribution functions (EEDFs) are measured at various argon pressures in an inductively coupled plasma. The measured plasma density versus coil current shows that the hysteresis during the E-H transition is clearly observed only when the pressure is sufficiently high. At low gas pressures the hysteresis is not obvious. The measured EEDFs show that when the hysteresis is obvious (high pressures), electrons whose energy is not sufficient for excitation or ionization of the ground state atom are strongly depleted in the H mode. This depletion may be caused by multistep ionization. However, for the case where the hysteresis is not obvious (low pressures), the depletion due to multistep ionization is also not present. These experimental results show that the multistep ionization is a dominant factor in the E-H transition hysteresis.},
doi = {10.1063/1.2734501},
journal = {Applied Physics Letters},
number = 19,
volume = 90,
place = {United States},
year = {Mon May 07 00:00:00 EDT 2007},
month = {Mon May 07 00:00:00 EDT 2007}
}
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